Fire-resistant composite panel and fire-resistant decorative composite panel using the same

ABSTRACT

The present invention relates to a fire-resistant composite panel having superior fire-resistance and impact-resistance, a low dimensional change, and good workability to form a curvature, and it also relates to a fire-resistant decorative composite panel using the same. The composite panel comprises a substrate layer formed by impregnating or coating a substrate material of a woven or nonwoven fabric of inorganic fiber, or a paper, with a resin compound that contains an inorganic filler having less as a component and a thermosetting resin, and a rear layer of an aluminum sheet or a galvanized steel plate.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a fire-resistant composite panel, andmore particularly, to a fire-resistant composite panel that can be usedin various applications such as for interior finishing materials forpassenger cars, interior materials for ships and automobiles, materialsfor walls of subway stations, washrooms and kitchens, building interioror exterior materials for ceilings and floors, and for furniture, thefire-resistant composite panel having excellent fire-resistance andimpact-resistance, a low dimensional change, and good workability toform a curvature. The present invention also relates to a fire-resistantdecorative composite panel using the fire-resistant composite panel.

(b) Description of the Related Art

A common melamine-based decorative panel is generally formed by pressinga plurality of layers consisting of a surface protective layer and adecoration layer both impregnated by a melamine resin, and a core layerimpregnated by a phenol resin onto kraft paper, using a multi-stagepress at an elevated temperature under a high pressure. However, thesedecorative panels have drawbacks of being thermally weak due to theirhigh content of resins and pulp layers.

Therefore, in order to meet the requirement of fire-resistance formaterials used as building interior and exterior materials, furniture,and the like, ground stone or processed metals are used, andalternately, tiles made of ceramics or porcelain are attached to thesurface. Though these materials have good durability andfire-resistance, they have drawbacks of a high manufacturing cost, aheavy weight, and low workability; and furthermore there is limitationfor their use as colorful decoration.

In order to solve the above-mentioned problems, fire-resistantmelamine-based decorative materials comprising a specific inorganiccompound in their substrate layer have been proposed, examples of whichcan be found in Japanese Patent Pub. Nos. 03-253342 (FIG. 1), 11-268186(FIG. 2), 10-305527 (FIGS. 2 and 3), 10-305525 (FIGS. 2 and 3), etc.These decorative panels have a multi-layered configuration consistingof, from top to bottom, a sheet for a decorative layer using a patternedsubstrate and a melamine resin, a basic material layer made by blendingan inorganic filler such as a nonwoven glass fabric and aluminumhydroxide with a melamine resin or a phenol resin and by impregnating orcoating, a reinforcing layer made by blending and impregnating anonwoven glass fabric with a melamine resin or a phenol resin, anotherbasic material layer and another decorative layer. These layers aremolded with a multi-stage press at a high temperature under a highpressure.

However, although such conventional fire-resistant melamine-baseddecorative panels exhibit improved fire-resistance compared with commonmelamine-based decorative panels, there are still problems in that theirfire-resistance and dimensional stability are insufficient because alarge amount of resin is used in order to improve strength andprocessability of the decorative panels and their manufacturing cost isincreased due to the use of inorganic filler such as aluminum hydroxide.

Moreover, the conventional fire-resistant melamine-based decorativepanel does not have enough impact resistance to be used alone when itsthickness is not more than 2 mm, and it can not be used to construct acurved surface.

SUMMARY OF THE INVENTION

Taking into consideration of the problems of the prior arts, an objectof the present invention is to provide a fire-resistant composite panelhaving excellent fire-resistance, impact-resistance and dimensionalstability; and also to provide a fire-resistant decorative compositepanel using the same.

Another object of the present invention is to provide a fire-resistantcomposite panel comprising a rear layer that imparts superiorflexibility to the panel itself thereby enabling working it to a curvedshape, and to provide a fire-resistant decorative composite panel usingthe same.

Yet another object of the present invention is to provide afire-resistant composite panel comprising an inorganic filler thatimparts superior strength to the decorative panel, and to provide afire-resistant decorative composite panel using the same.

In order to achieve these objects and others, the present inventionprovides a fire-resistant composite panel comprising:

a) a substrate layer formed by impregnating or coating a substratematerial of a woven or nonwoven fabric of inorganic fiber, or a paper,with a resin compound which contains an inorganic filler having loess asa main component and a thermosetting resin selected from the groupconsisting of a phenol resin a modified phenol resin, a modifiedphenol-urea resin, a melamine resin, and a modified melamine resin; and

b) a rear layer of an aluminum sheet or a galvanized steel plate.

Further, the present invention provides a fire-resistant decorativecomposite panel comprising:

a) a decoration layer formed by impregnating or coating a thermosettingresin onto a patterned substrate;

b) a substrate layer formed by impregnating or coating a substratematerial of a woven or nonwoven fabric of inorganic fiber, or a paper,with a resin compound which contains an inorganic filler having loess asa main component and a thermosetting resin selected from the groupconsisting of a phenol resin, a modified phenol resin, a modifiedphenol-urea resin, a melamine resin, and a modified melamine resin; and

c) a rear layer of an aluminum sheet or a galvanized steel plate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a conventional fire-resistant decorativematerial.

FIG. 2 is a sectional view of a conventional fire-resistant decorativepanel.

FIG. 3 is a sectional view of another conventional fire-resistantdecorative panel.

FIG. 4 is a sectional view of a general melamine-based decorativealuminum composite panel according to Comparative Example 2.

FIG. 5 is a sectional view of a fire-resistant decorative compositepanel according to Example 1.

FIG. 6 is a sectional view of a fire-resistant decorative compositepanel according to Example 2.

FIG. 7 is a sectional view of a fire-resistant decorative compositepanel according to Example 3.

FIG. 8 is a sectional view of a fire-resistant decorative compositepanel according to Example 4.

FIG. 9 is a sectional view of a fire-resistant decorative compositepanel according to Example 5.

FIG. 10 is an explanatory diagram of fabricating a fire-resistantcomposite panel according to the present invention into a curvedsurface.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will be explained more specifically in thefollowing.

The present invention provides an integrated fire-resistant compositepanel formed by superposing an aluminum sheet or a galvanized steelplate on the rear surface of a substrate material and then molding themat a high temperature under a high pressure, wherein the substratematerial is made by stacking one or more sheets impregnated or coated ona substrate of woven or nonwoven fabric made from an inorganic fibersuch as glass fiber or alumina fiber, or a paper, with the resincompound including an inorganic filler having loess as a main component,and a phenol resin, a modified phenol resin, a modified phenol-urearesin, a melamine resin, or a modified melamine resin, containing a goodfire retardant.

The fire-resistant composite panel according to the invention hassuperior fire-resistance, impact-resistance and dimensional stability;and good workability of its rear layer enables the panel to be formed ina curve.

The present invention also provides a fire-resistant decorativecomposite panel having a decorated surface by integrating a patternedsheet that is impregnated with a thermosetting resin such as a melamineresin on the surface of the above-mentioned fire-resistant compositepanel that is used as a substrate layer.

Further, a fire-resistant composite panel and a fire-resistantdecorative composite panel according to the present invention may have areinforcing layer interposed between the substrate layer and thedecoration layer, between each of the substrate layers, or between thesubstrate layer and the rear layer, the reinforcing layer being formedby impregnating or coating a woven inorganic fiber such as glass fiberor alumina fiber, or kraft paper with a resin compound of athermosetting resin such as fire-resistant modified melamine resin ormodified phenol resin.

The substrate layer and the reinforcing layer may be used in multiplelayers, the configuration of which can be varied according to theapplication and thickness thereof. Particularly, if they are used as awall body, they are preferably prepared to have a thickness of 2 to 5mm, and in this case the number of substrate layers may be 1 to 5 sheetsand the number of reinforcing layers may be 1 to 12 sheets depending onthe necessity. The thickness of the rear layer is preferred to be in therange of 0.2 to 2 mm in order to facilitate working into a curvature.

When the fire-resistant composite panel is formed into a fire-resistantdecorative composite panel, it may be subject to various methods ofdecoration. The decoration methods include, as typical examples, coatingthe surface of the fire-resistant composite panel with paint and thelike, and impregnating or coating the decoration layer with athermosetting resin and the like as described above and then attachinthe treated layer to the surface of the fire-resistant panel. Thedecorative composite panel may be specifically named a melaminedecorative composite panel, a phenol decorative composite panel, anacryl-based decorative composite panel, or a urethane-based decorativecomposite panel in accordance with the kind of resin contained in thefinish coat applied or the kind of thermosetting resin impregnated inthe decoration layer such as melamine resin, phenol resin, acryl resin,or urethane resin.

A decorative composite panel more suitable for use of a fire-resistantcomposite panel of the present invention is a panel which has afire-resistant property imparted to its surface and, considering thatthe fire-resistant composite panel is a thermosetting resin, the panelis made by superposing a decoration layer impregnated or coated with athermosetting resin and the like on the surface of a patterned paper,and then heat-pressing to effect attachment.

The types of decorative composite panels according to the invention aredescribed in the following.

As a first type, a fire-resistant decorative composite panel using loesscomprises, from top to bottom (FIG. 5):

i) a decoration layer;

ii) 1 to 5 substrate layers; and

iii) a rear layer.

As a second type, a fire-resistant decorative composite panel usingloess comprises, from top to bottom (FIG. 6):

i) a decoration layer;

ii) 1 to 5 substrate layers;

iii) 1 to 12 reinforcing layers; and

iv) a rear layer.

As a third type, a fire-resistant decorative composite panel using loesscomprises, from top to bottom (FIG. 7):

i) a decoration layer;

ii) 1 to 12 reinforcing layers;

iii) 1 to 5 substrate layers; and

iv) a rear layer.

As a fourth type, a fire-resistant decorative composite panel usingloess comprises, from top to bottom (FIG. 8):

i) a decoration layer;

ii) 1 to 5 substrate layers;

iii) 1 to 12 reinforcing layers;

iv) 1 to 5 substrate layers; and

v) a rear layer.

As a fifth type, a fire-resistant decorative composite panel using loesscomprises, from top to bottom (FIG. 9):

i) a decoration layer;

ii) 1 to 12 reinforcing layers;

ii) 1 to 5 substrate layers;

iv) 1 to 12 reinforcing layers; and

v) a rear layer.

A fire-resistant composite panel according to the present invention alsohas a configuration of the afore-mentioned five types of fire-resistantdecorative composite panels such that a decoration layer as the toplayer is not included, but a substrate layer is intended to be the toplayer. Such a fire-resistant composite panel is fabricated withoutdecorating, and the decoration may be performed by a separate process orby a separate paint coating and the like at the installation site.

In the following, the above layers are explained, respectively.

The substrate layer is a sheet shaped layer formed by impregnating orcoating a substrate material of a woven or nonwoven fabric of inorganicfiber, or a paper, with a resin compound which contains an inorganicfiller having loess as a main component and a phenol resin, a modifiedphenol resin, a modified phenol-urea resin, a melamine resin, or amodified melamine resin.

The substrate material for the substrate layer is preferably a woven ornonwoven fabric of inorganic fibers such as glass fiber or aluminafiber, or a paper such as kraft paper. Particularly, a preferredsubstrate material is a nonwoven fabric of glass fiber that is made bychopping a glass fiber having a composition of E-glass with a fiberdiameter of 6 to 30 μm into a length of 10 to 50 mm using a needlingmachine, and then by blending a binder such as an epoxy resin, an acrylresin, or a polyvinyl alcohol resin therein.

The substrate material preferably has weight per unit area of 30 to 200g/m². When the weight per unit area is less than 30 g/m², problems maybe caused during impregnating, coating, forming or handling due toinsufficient strength of the decorative panel made. On the other hand,when the weight per unit area exceeds 200 g/m², the panel becomes hardand efficiency of impregnation or coating as well as workability islowered.

It is preferred that the resin compound of modified melamine resin ormodified phenol resin impregnated into the substrate material for thesubstrate layer comprises:

i) 3.0% to 10.0% by weight (based on solid mass) of a first condensateof melamine or phenol resin;

ii) 50% to 80% by weight of loess;

iii) 1.0% to 5.0% by weight of fire retardant; and

iv) 10% to 40% by weight of solvent(water or alcohol).

Specifically, when the compound contains not more than 5% by weight ofthe modified melamine resin or modified phenol resin and more than 4.0%by weight of the fire retardant, it can be classified as Grade 1 for afire-resistance test according to Korean Standard No. KS F 2271 entitled“Testing method for incombustibility of internal finish materials andelements of building.”

In the resin compound, a part of the loess to be used as an inorganicfiller may be replaced by an alternative inorganic filler selected fromthe group consisting of aluminum hydroxide, magnesium hydroxide andtalc, in order to improve workability after the process ofpress-forming.

In such a case, the composition of the resin compound preferablycomprises:

i) 3.0% to 10.0% by weight (based on solid mass) of a first condensateof melamine or phenol resin;

ii) 40% to 70% by weight of loess;

iii) 3% to 20% by weight of an alternative inorganic filler selectedfrom the group consisting of aluminum hydroxide, magnesium hydroxide andtalc;

iv) 1.0% to 5.0% by weight of fire retardant; and

v) 10% to 40% by weight of solvent (water or alcohol).

The resin compound may be used as it is or with the addition of adiluent such as water or alcohol. The amount of the resin compound to beimpregnated (or coated) is preferably 400 to 2000 parts by weight basedon 100 parts by weight of the substrate material. If the impregnatedamount is less than 400 parts by weight, more sheets are required toadjust the specified thickness and the cost will be increased, whereasif the amount exceeds 2000 parts by weight, drying time is extended tothereby lower the productivity, and inter-layer adhesive strength afterpress-forming may also become weak.

The modified melamine resin and modified phenol resin are liquid-phaseresins, and they are the first condensates prepared by a usualpolymerization process using 25% to 45% by weight of melamine or phenol,30% to 60% by weight of formaldehyde, 2% to 5% by weight of aplasticizer and 10% to 25% by weight of distilled water as a solvent. Inthe case of using the melamine resin, a curing agent may be furtheradded in order to reduce the time required for curing.

As the fire retardant, a liquid phase fire retardant containing phosphorand nitrogen and a solid phase fire retardant, dicyandiamide, may beused in combination. The charging method is preferably carried out byadding 100 parts by weight of the first condensate, 15 to 30 parts byweight of fire retardant containing phosphor/nitrogen, and 5 to 10 partsby weight of dicyandiamide as a solid phase fire retardant. By means ofaddition of these fire retardants, the resin will acquire fire-resistantproperties.

A preferable example of the liquid phase fire retardant containingphosphor and nitrogen is Melflam 131 A (product of SKW Trostberg,Germany), which is an aqueous solution containing nitrogen and phosphorand which contains 35% to 45% by weight of active components. A functionof this fire retardant is to produce polymerized polyphosphoric acid bypromoting thermal polycondensation of polyphosphoric acid if thedecorative panel is subjected to a high temperature when a fire breaksout, and the thus-produced polymeric polyphosphoric acid will then actas a dehydrogenation catalyst to form charcoal, and thereby oxygen andheat will be interrupted and superior nonflammable effects are thenceexhibited. Further, many kinds of nitrogen components contained in themelamine resin also assist in the production of polymeric polyphosphoricacid. When such a liquid phase fire retardant containing phosphor andnitrogen is used together with dicyandiamide as a solid phase fireretardant, the effect will be doubled by virtue of fire-resistantsynergism.

Dicyandiamide is a solid and it reacts with various materials containedin the resin compound such as formaldehyde, water, and ammonium salt tochange them into a nonflammable substance, thereby resulting infire-resistant effects that exclude the ability of the decorative panelto burn if it is subjected to a high temperature when a fire breaks out.Particularly, when it is used together with a liquid phase fireretardant containing phosphor and nitrogen, the effect will be doubledby virtue of fire-resistant synergism as previously noted.

Loess as an inorganic filler does not transfer heat if the decorativepanel is subjected to a high temperature when a fire breaks out, andadditionally the water of crystallization contained within the loesscomponent absorbs heat to provide a fire-resistant effect. Furthermore,loess effects a uniform heat transfer to the resin during the formationof the decorative panel under a condition of high temperature and highpressure, and it provides good adhesion between each layer.

In general, loess is known to have pharmaceutical efficacy such asdetoxifying potential or antibacterial effects, and it is widely used asa purifying agent against environmental pollutants, for cosmeticmaterials and as therapeutics for folk remedies. As loess has acapability of infrared irradiation in addition to its conventional uses,it can provide a warming effect to the human body as well as thermalinsulation to buildings when it is included within the composite panelaccording to the present invention.

Loess used in the present invention exhibits different colors such aswhite, yellow or red depending on the district of its origin, and it isfound in Korea at Sancheong in Gyeongsangnam-do, Chongdo inGyeongsangbuk-do, Gurye or Hwasun in Jeollanam-do and Buan inJeollabuk-do is particularly preferred. Preferably, the loess has acomposition of 10% to 90% by weight of silicon dioxide, 10% to 80% byweight of aluminum oxide, 0.1% to 50% by weight of iron oxide, 0.1% to30% by weight of magnesium oxide, 0.1% to 50% by weight of calciumoxide, 0.1% to 30% by weight of potassium oxide, 0.1% to 5% by weight ofmineral oxide and inorganic material, 0% to 5% by weight of moisture and0.1% to 20% by weight of impurities as a remainder.

Loess used in the present invention may be natural loess itself or acalcined loess which has been treated by calcining at a temperature of300° to 1000° C. Such calcined loess is obtained by eliminating organiccompounds contained therein and then by reducing irregularly scatteredmicropores as well as water of crystallization to a certain level. Suchcalcined loess can be used in further increased quantities because ithas a reduced amount of oil absorption during blending with resin, thusproviding better fire-resistant properties.

The particle size distribution of loess used as an inorganic filler inthe present invention is preferably 5 to 300 μm, while its mean particlesize is preferably 10 to 50 μm. If loess with particle size below theabove range is used, the viscosity of the resin will become high due tostrong oil absorptivity of resin and solvent so that efficiency ofimpregnation or coating workability is lowered. On the other hand, ifloess with a particle size of over the above range is used, smoothnessof the panel surface may be reduced by the presence of large particleson the surface during the formation of the decorative panel under acondition of high temperature and high pressure after impregnation orcoating.

The particle size of the alternative inorganic filler such as aluminumhydroxide, magnesium hydroxide or talc which is used to replace a partof the loess is preferably in the range of 10 to 50 μm. If an inorganicfiller with a particle size below the above range is used, the resinviscosity will become high due to strong oil absorptivity of resin andsolvent so that workability is lowered. On the other hand, if aninorganic filler with a particle size of over the above range is used,smoothness of panel surface may be reduced by the presence of largeparticles on the surface after the product is formed.

The composite panel and the decorative composite panel according to thepresent invention can be made to have a reinforcing layer interposedbetween the substrate layer and the decoration layer, between eachsubstrate layers, or between the substrate layer and the rear layer,wherein the reinforcing layer is formed by impregnating or coating awoven or nonwoven fabric of inorganic fiber such as glass fiber andalumina fiber, or kraft paper with modified melamine resin or modifiedphenol resin.

In the case the substrate material of the reinforcing layer is wovenfabric, its weight per unit area is preferably in the range of 30 to 150g/m². If the weight per unit area is less than 30 g/m², the thickness ofthe fiber will not be sufficient such that it will be too pliable andits handling and workability during lamination will be poor. On theother hand, if the weight per unit area is more than 150 g/m², the fiberwill become too thick such that marks of the fibers may be transcribedto the surface of the panel upon production, and the adhesive strengthwill become too weak such that separation of the layers may occur. Thewoven fabric of inorganic fiber used as a substrate material for thereinforcing layer is preferably a woven fabric of glass fiber having anE-glass composition, made by means of a weaving machine.

In the case the substrate material of the reinforcing layer is kraftpaper, its weight per unit area is preferably 70 to 300 g/m². If theweight per unit area is less than 70 g/m², workability such asimpregnation and lamination will become worse, and on the other hand, ifthe weight per unit area is more than 300 g/m², it will be difficult toadjust thickness required in the panel production and the adhesivestrength between upper and lower layers will become too weak such thatseparation of the layers may occur.

The reinforcing layer is prepared by impregnating (or coating) 100 partsby weight of a woven fabric of inorganic fiber or kraft paper with 40 to200 parts by weight of the compound of modified melamine resin ormodified phenol resin which is used in the substrate layer.Alternatively, impregnation can be carried out with 40 to 100 parts byweight of modified melamine resin alone or modified phenol resin alone,both containing no inorganic loess filler. However, the greater theamount of resin used, the worse the fire-resistance will be.

The decoration layer used in the decorative composite panel according tothe present invention has a sheet shape, and it comprises athermosetting resin sheet made by impregnating or coating 100 parts byweight of a paper substrate having a weight per unit area of 40 to 200gm². The substrate is made of synthetic pulp, wood, textile fabrics,organic synthetic fiber and the like with 50 to 200 parts by weight of aresin such as melamine resin, phenol resin, acryl resin and urethaneresin. When an inorganic component such as titanium oxide is blended inthe substrate material of the decoration layer, fire-resistance may beenhanced, and using a lesser amount of resin is advantageous forfire-resistance.

The rear layer used in the present invention is an aluminum sheet or agalvanized steel plate, which has superior strength, corrosionresistance and workability so that tie panel is suitable for use as aninternal finish material for passenger cars, ships, automobiles and thelike. In particular, the preferred alloy material of the aluminum sheetis A1050, A3004 or A5052, but it is not limited to them. It is desirablethat the aluminum sheet or galvanized steel plate is coated with variouskinds of thermosetting resins on its surface in order to facilitate anintegrated formation thereof with the substrate material byheat-pressing.

The rear layer described above enables the composite panel and thedecorative composite panel to be worked into a curvature, and it impartsa high impact-resistance upon them. The radius of curvature thatindicates a degree of curvature-forming is different according to thethickness of the rear layer(31). In the case the thickness of the rearlayer is 0.5 to 2 mm, when it is positioned at the rear side of an upperlayer(51) (example of the type with: substrate layer, decorationlayer/substrate layer, decoration layer/reinforcing layer/substratelayer, decoration layer/substrate layer/reinforcing layer/substratelayer, etc.) having a thickness of 0.4 to 1.0 mm and these layers areintegrally formed by means of heat-press, a curvature working up to aradius of curvature of 30 mm is possible, as shown in FIG. 10. Whencurvature working is done without such a rear layer or the material isbent simply by force, it will be broken because of insufficient dragforce of the substrate layer or the decoration layer.

The fire-resistant composite panel and fire-resistant decorativecomposite panel according to the present invention are produced bypreparing individual layers, then superposing these layers andheat-pressing them with a multistage press. In this process, it ispreferable to use a plurality of sheets for the substrate andreinforcing layers in consideration of panel thickness, with a singlesheet of the decoration layer being used for each surface. In addition,if a mirror plate, embossed plate, or the like is superposed on theproduct surface when forming is done by heat-pressing, an embossingeffect may be provided.

The fire-resistant composite panel and fire-resistant decorativecomposite panel according to the present invention have at least threetimes higher impact-resistance as well as equivalently good dimensionalstability when compared with a conventionally-made melamine-basedfire-resistant panel having a thickness of 2.0 to 4.5 mm. Therefore, thedecorative composite panel itself can be attached on a wall or a frameof steel or wood, or the like, by means of adhesives, screws, nails,etc. without using any separate reinforcing plate material. Thefire-resistant decorative composite panel according to the presentinvention is designed for attachment in such a manner that thedecoration layer is oriented to face outward in order to enable thedecorative surface to be seen from outside.

The fire-resistant composite panel and the fire-resistant decorativecomposite panel have excellent fire-resistance and impact-resistance,and they exhibit a low dimensional change, so they can be suitably usedin various applications such as for internal finish materials forpassenger cars, interior materials for ships and automobiles, materialsfor walls of subway stations, washrooms and kitchens, building interioror exterior materials for ceilings and floors, for the floor ofpassenger cars, and furniture, and as they can be worked to form acurvature, their application field is quite broad.

The present invention will be described in further detail with referenceto the following examples and comparative examples. However, theexamples are intended to be illustrative of the present invention, andthe present invention is not to be limited to them.

EXAMPLES Example 1

(Preparation of a Compound of a Fire-resistant Melamine Resin and Loessfor a Substrate Layer and a Fire-resistant Kraft Layer)

1.7 mol of formaldehyde was added to 1 mol of melamine and the mixturewas reacted at 95° C. under a weak alkaline condition, and then thecontent of the reagents was controlled by adding a plasticizer and waterto obtain an initial condensation product. 0.1 parts by weight ofparatoluenesulfonic acid (PTSA) as a hardener and 0.1 parts by weight ofMelpers RH4 (product of SKW Trostberg, Germany) as a potential hardener(a hardener which promotes reaction exclusively at a high temperature)were added to 100 parts by weight of this initial condensation productto obtain a melamine resin. 20 parts by weight of Melflam 131A as aliquid fire retardant and 4.0 parts by weight of dicyandiamide as asolid fire retardant were added to 100 parts by weight of the melamineresin to obtain a fire-resistant melamine resin.

900 parts by weight of loess having an average particle size of 10 to 50μm were added to 100 parts by weight of the above-obtainedfire-resistant melamine resin to prepare a resin compound offire-resistant melamine resin and loess.

(Preparation of a Substrate Layer Sheet)

Nonwoven fabric of E-glass fiber with a weight per unit area of 110 g/m²obtained by treatment of the above resin compound of fire-resistantmelamine resin and loess with acryl resin-based binder was impregnatedand it was dried to prepare a substrate layer sheet having a degree ofimpregnation of 800% by weight based on dry weight.

(Preparation of a Melamine Resin for Decoration Layer)

1.7 mol of formaldehyde was added to 1 mol of melamine and the mixturewas reacted at 95° C. under a weak alkaline condition, and then thecontent of the reagents was controlled by adding water to obtain aninitial condensation product. 0.2 parts by weight of paratoluenesulfonicacid (PTSA) as a hardener and 0.2 parts by weight of Melpers RH4(product of SKW Trostberg, Germany) as a potential hardener (a hardenerwhich promotes reaction exclusively at a high temperature) were added to100 parts by weight of this initial condensation product to prepare amelamine resin.

(Preparation of a Decoration Layer Sheet)

The above-obtained melamine resin was impregnated to 90% by weight intoprinted patterned paper of 80 g/m² into which titanic oxide wasincorporated, and a decoration layer sheet was obtained.

(Preparation of a Rear Layer Sheet)

A melamine-based thermosetting resin binder was uniformly coated to athickness of 0.05 to 0.2 mm on the surface of a 0.8 mm thick aluminumsheet, and then the coated sheet was completely dried under a naturalenvironment to prepare a rear layer.

(Preparation of a Fire-resistant Decorative Composite Panel: FIG. 5)

The above-obtained sheets were stacked from top to bottom in the orderof 1 sheet of the decoration layer, 1 sheet of the substrate layersheet, and 1 sheet of the rear layer, and then a mirror plate ofstainless steel was superposed on the decoration layer. It was allsubjected to heat-pressing at a temperture of 150° C. and a pressure of100 kgf/cm² for 30 minutes, and thus a fire-resistant melamine-baseddecorative aluminum composite panel having a thickness of 1.5 mm wasprepared.

Example 2

(Preparation of a Compound of a Fire-resistant Phenol Resin and Loessfor a Substrate Layer and a Reinforcing Layer)

1.4 mol of formaldehyde was added to 1 mol of phenol and the mixture wasreacted at 100° C. under a weak alkaline condition, and then the contentof the reagents was controlled by adding water to obtain an initialcondensation product. 20 parts by weight of Melflam 131A as a liquidfire retardant and 4.0 parts by weight of dicyandiamide as a solid fireretardant were added to 100 parts by weight of this initial condensationproduct to obtain a fire-resistant phenol resin.

900 parts by weight of loess having an average particle size of 10 to 50μm was added to 100 parts by weight of the above-obtained fire-resistantphenol resin to prepare a resin compound of fire-resistant phenol resinand loess.

(Preparation of a Substrate Layer Sheet)

Nonwoven fabric of E-glass fiber with a weight per unit area of 110 g/m²obtained by treatment with acryl resin-based binder was impregnated withthe above resin compound of fire-resistant phenol resin and loess, andit was dried to prepare a substrate layer sheet having a degree ofimpregnation of 800% by weight based on dry weight.

(Preparation of a Decoration Layer Sheet)

A decoration layer sheet as in Example 1 was prepared.

(Preparation of a Reinforcing Layer Sheet)

Nonwoven fabric of E-glass fiber with a weight per unit area of 60 g/m²was impregnated with the above resin compound of fire-resistant phenolresin and loess, and it was dried to prepare a reinforcing layer sheetof 300% by weight based on dry weight.

(Preparation of a Rear Layer Sheet)

A phenol-based thermosetting resin binder was uniformly coated to athickness of 0.05 to 0.2 mm on the surface of a 0.4 mm thick galvanizedmetal plate, and then the coated plate was completely dried under anatural environment to prepare a rear layer.

(Preparation of a Fire-resistant Decorative Composite Panel: FIG. 6)

The above-obtained sheets were stacked from top to bottom in the orderof 1 sheet of the decoration layer, 1 sheet of the substrate layer, 1sheet of the reinforcing layer, and 1 sheet of the rear layer, and thena mirror plate of stainless steel was superposed on the decorationlayer. It was all subjected to heat-pressing at a temperature of 150° C.and a pressure of 100 kgf/cm² for 30 minutes, and thus a fire-resistantmelamine-based decorative galvanized steel composite panel having athickness of 1.5 mm was prepared.

Example 3

(Preparation of a Substrate Layer Sheet)

A substrate layer sheet as in Example 2 was prepared.

(Preparation of a Sheet of Reinforcing Layer and Fire-resistant KraftLayer)

A fire-resistant kraft paper was impregnated to a weight per unit areaof 300 g/m² with the fire-resistant phenol resin prepared in Example 2and dried to prepare a fire-resistant kraft layer sheet of 80% by weightbased on dry weight.

(Preparation of a Decoration Layer Sheet)

The fire-resistant phenol resin prepared in Example 2 was impregnated to90% by weight into printed patterned paper of 80 g/m² into which titanicoxide was incorporated, and a decoration layer sheet was obtained.

(Preparation of a Rear Layer Sheet)

A phenol-based thermosetting resin binder was uniformly coated to athickness of 0.05 to 0.2 mm on the surface of a 0.4 mm thick aluminumsheet, and then the coated sheet was completely dried under a naturalenvironment to prepare a rear layer.

(Preparation of a Fire-resistant Decorative Composite Panel: FIG. 7)

The above-obtained sheets were stacked from top to bottom in the orderof 1 sheet of the decoration layer, 1 sheet of the reinforcing layer, 1sheet of the substrate layer sheet, and 1 sheet of the rear layer, andthen a mirror plate of stainless steel was superposed on the decorationlayer. It was all subjected to heat-pressing at a temperature of 150° C.and a pressure of 100 kgf/cm² for 30 minutes, and thus a fire-resistantphenol-based decorative aluminum composite panel having a thickness of1.5 mm was prepared.

Example 4

(Preparation of a Substrate Layer Sheet)

A substrate layer sheet as in Example 1 was prepared.

(Preparation of a Reinforcing Layer Sheet and a Fire-resistant KraftLayer)

A fire-resistant kraft paper was impregnated to a weight per unit areaof 300 g/m² with the fire-resistant phenol resin prepared in Example 2and dried to prepare a fire-resistant kraft layer sheet of 80% by weightbased on dry weight.

(Preparation of a Decoration Layer Sheet)

A decoration layer sheet as in Example 1 was prepared.

(Preparation of a Rear Layer Sheet)

A rear layer sheet as in Example 1 was prepared.

(Preparation of a Fire-resistant Decorative Composite Panel: FIG. 8)

The above-obtained sheets were stacked from top to bottom in the orderof 1 sheet of the decoration layer, 3 sheets of the substrate layersheet, 3 sheets of the fire-resistant kraft layer sheet, 3 sheets of thesubstrate layer sheet and 1 sheet of the rear layer, and then a mirrorplate of stainless steel was superposed on each surface. The stackedsheets were then subjected to heat-pressing at a temperature of 150° C.and a pressure of 100 kgf/cm² for 30 minutes, and thus a fire-resistantmelamine-based decorative aluminum composite panel having a thickness of4.5 mm was prepared.

Example 5

(Preparation of a Substrate Layer Sheet)

A substrate layer sheet as in Example 1 was prepared.

(Preparation of a Sheet of Reinforcing Layer and Fire-resistant KraftLayer)

A fire-resistant kraft paper was impregnated to a weight per unit areaof 300 g/m² with the fire-resistant phenol resin prepared in Example 2and dried to prepare a fire-resistant kraft layer sheet of 80% by weightbased on dry weight.

(Preparation of a Decoration Layer Sheet)

A decoration layer sheet as in Example 1 was prepared.

(Preparation of a Rear Layer Sheet)

A rear layer sheet as in Example 1 was prepared.

(Preparation of a Fire-resistant Decorative Composite Panel: FIG. 9)

The above-obtained sheets were stacked from top to bottom in the orderof 1 sheet of the decoration layer, 3 sheets of the fire-resistant kraftlayer sheet, 3 sheets of the substrate layer sheet, 3 sheets of thefire-resistant kraft layer sheet, and 1 sheet of the rear layer, andthen a mirror plate of stainless steel was superposed on each surface.The stacked sheets were then subjected to heat-pressing at a temperatureof 150° C. and a pressure of 100 kgf/cm² for 30 minutes, and thus afire-resistant melamine-based decorative aluminum composite panel havinga thickness of 4.5 mm was prepared.

Comparative Example 1

(Preparation of a Substrate Layer Sheet)

A substrate layer sheet was prepared in the same manner as in Example 1except that aluminum hydroxide having a particle size of 10 to 50 μm wasused instead of loess as an inorganic filler.

(Preparation of a Decoration Layer Sheet)

A decoration layer sheet as in Example 1 was prepared.

(Preparation of a Fire-resistant Melamine-based Decorative Panel: FIG.1)

In the same manner as in Example 1, the above-obtained sheets werestacked from top to bottom in the order of 1 sheet of the decorationlayer, 7 sheets of the substrate layer sheet and 1 sheet of thedecoration layer, and then a mirror plate of stainless steel wassuperposed on each surface. The stacked sheets were then subjected toheat-pressing at a temperature of 150° C. and a pressure of 100 kgf/cm²for 30 minutes, and thus a fire-resistant melamine-based decorativepanel having a thickness of 4.5 mm was prepared.

Comparative Example 2

(Preparation of a Decoration Layer and a Kraft Layer)

A decoration layer as in Example 1 and a melamine resin impregnatedkraft layer for an ordinary melamine-based decorative plate wereprepared as a substrate layer.

(Preparation of a Rear Layer Sheet)

A thermosetting resin binder was uniformly coated to a thickness of 0.05to 0.2 mm on the surface of a 1.0 mm thick aluminum sheet, and then thecoated sheet was completely dried under a natural environment to preparea rear layer.

(Preparation of an Ordinary Melamine-based Decorative Aluminum CompositePanel: FIG. 4)

The above-obtained sheets were stacked from top to bottom in the orderof 1 sheet of the decoration layer, 3 sheets of the phenol resinimpregnated kraft sheet (substrate layer), and 1 sheet of the rearlayer, and then a mirror plate of stainless steel was superposed on thesurface of the decoration layer. The stacked sheets were then subjectedto heat-pressing at a temperature of 150° C. and a pressure of 100kgf/cm² for 30 minutes, and thus an ordinary melamine-based decorativealuminum composite panel having a thickness of 1.5 mm was prepared.

The physical properties of each of the fire-resistant decorativecomposite panels prepared in Examples 1 to 5 and Comparative Examples 1and 2 were compared, and the results are summarized in the followingTable 1.

TABLE 1 Comp. Comp. Example Example Example Example Example ExampleExample 1 2 3 4 5 1 2 Fire- Surface passed passed Passed passed passedpassed passed resistance test Substrate passed passed Passed passedpassed passed not Test passed Dimensional stability 1 −0.03% −0.03%−0.03% −0.06% −0.06% −0.10% −0.10% (70° C., 24 hr) Dimensional stability2 +0.01% +0.01% +0.01% +0.03% +0.04% +0.05% +0.02% (45° C., 95% RH, 96hr) Impact-resistance (Dropping test with  900 mm  900 mm  900 mm  900mm  900 mm   200 mm  900 mm 67 g iron ball) Thickness  1.5 mm  1.5 mm 1.5 mm  4.5 mm  4.5 mm  4.5 mm  1.5 Min. radius of   30 mm   30 mm   30mm   70 mm   70 mm  1200 mm   30 mm curvature (R)

In the above table, fire-resistance data represent results of a testcarried out in accordance with “Testing method for incombustibility ofinternal finish materials and elements of building” as set forth in KSF2271, and the dimensional stability data represent results of a testcarried out according to “Testing method for laminated thermosettinghigh-pressure decorative sheets” as set forth in JIS K 6902.

Further, the minimum radius of curvature represents the radius ofcurvature (R) of the decoration layer measured in such a way that thepanel was held by both ends and the ends were pulled together to bendthe decoration layer until it just resisted breakage.

The fire-resistant composite panel and the fire-resistant decorativecomposite panel prepared by using loess according to the presentinvention comprise a substrate layer integrally formed with a compoundof a melamine resin, a phenol resin, or a modified resin, which includesloess, and a porous sheet such as a woven or nonwoven fabric made ofinorganic fibers, for example glass or alumina fibers, or kraft paper asmain inorganic fillers, with the addition of a fire retardant. They alsocomprise an aluminum sheet or a galvanized steel plate as a rearreinforcing layer, and the resulting panels have superior dimensionalstability and impact-resistance. Therefore, the composite panelaccording to the invention can be used in various applications such asfor interior materials for passenger cars, interior materials for shipsand automobiles, materials for building interiors or exteriors, materialfor interiors, furniture and floors; and furthermore, the fire-resistantcomposite panel has excellent fire-resistance and impact-resistance aswell as a low dimensional change and good workability to form acurvature.

What is claimed is:
 1. A fire-resistant composite panel comprising: a) asubstrate layer formed by impregnating or coating a substrate materialof a woven or nonwoven fabric of inorganic fiber, or a paper, with aresin compound which contains an inorganic filler having loess as a maincomponent and a thermosetting resin selected from the group consistingof a phenol resin, a modified phenol resin, a modified phenol-urearesin, a melamine resin, and a modified melamine resin; and b) a rearlayer of an aluminum sheet or a galvanized steel plate.
 2. Afire-resistant composite panel according to claim 1, wherein areinforcing layer formed by impregnating or coating a woven inorganicfiber or kraft paper with a resin compound of a modified melamine resinor a modified phenol resin is interposed between substrate layers orbetween the substrate layer and the rear layer of the composite panel.3. A fire-resistant composite panel according to claim 1, wherein theamount of the resin compound impregnated into the substrate layer is 400to 2000 parts by weight with reference to 100 parts by weight of thesubstrate material.
 4. A fire-resistant composite panel according toclaim 1, wherein the resin compound comprises: i) 3.0% to 10.0% byweight (based on solid mass) of a first condensate of a melamine resinor a phenol resin which is produced by reaction of 25% to 45% by weightof melamine or phenol, 30% to 60% by weight of formaldehyde, 2% to 5% byweight of a plasticizer, and 10% to 25% by weight of water; ii) 50% to80% by weight of loess; iii) 1.0% to 5.0% by weight of fire retardant;and iv) 10% to 40% by weight of water or alcohol as a solvent.
 5. Afire-resistant composite panel according to claim 1, wherein the resincompound comprises: i) 3.0% to 10.0% by weight (based on solid mass) ofa first condensate of a melamine resin or a phenol resin which isproduced by reaction of 25% to 45% by weight of melamine or phenol, 30%to 60% by weight of formaldehyde, 2% to 5% by weight of a plasticizer,and 10% to 25% by weight of water; ii) 40% to 70% by weight of loess;iii) 3% to 20% by weight of one or more inorganic fillers selected fromthe group consisting of aluminum hydroxide, magnesium hydroxide andtalc; iv) 1.0% to 5.0% by weight of fire retardant; and v) 10% to 40% byweight of water or alcohol as a solvent.
 6. A fire-resistant decorativecomposite panel according to claim 1, wherein the loess has a particlesize distribution of 5 to 300 μm and a mean particle size of 10 to 50μm.
 7. A fire-resistant composite panel according to claim 1, whereinproduction areas of the loess in Korea include Sancheong inGyeongsangnam-do, Chongdo in Gyeongsangbuk-do, Gurye or Hwasun inJeollanam-do, and Buan in Jeollabuk-do.
 8. A fire-resistant compositepanel according to claim 1, wherein the loess has a composition of: 10%to 90% by weight of silicon dioxide, 10% to 80% by weight of aluminumoxide, 0.1% to 50% by weight of iron oxide, 0.1% to 30% by weight ofmagnesium oxide, 0.1% to 50% by weight of calcium oxide, 0.1% to 30% byweight of potassium oxide, 0.1% to 5% by weight of mineral oxide andinorganic material, 0% to 5% by weight of moisture and 0.1% to 20% byweight of impurities as a remainder.
 9. A fire-resistant composite panelaccording to claim 1, wherein the loess is calcined loess obtained bycalcining natural loess at a temperature of 300° to 1000° C.
 10. Afire-resistant composite panel according to claim 1, wherein thesubstrate material of the substrate layer is a woven or nonwoven fabricof glass fiber or alumina fiber, or kraft paper, and has a weight perunit area of 30 to 200 g/m².
 11. A fire-resistant composite panelaccording to claim 10, wherein the substrate material is a nonwovenfabric of glass fiber that is made by chopping a glass fiber having acomposition of E-glass with a fiber diameter of 6 to 30 μm into a lengthof 10 to 50 mm using a needling machine, and then by blending a binderselected from the group consisting of an epoxy resin, an acryl resin,and a polyvinyl alcohol resin with it.
 12. A fire-resistant compositepanel according to claim 2, wherein the amount of the resin compoundimpregnated into the reinforcing layer is 50 to 500 parts by weight withreference to 100 parts by weight of the substrate material.
 13. Afire-resistant composite panel according to claim 2, wherein the resincompound comprises: i) 3.0 to 10.0 parts by weight of a first condensateof a melamine resin or a phenol resin which is produced by reaction of25% to 45% by weight of melamine or phenol, 30% to 60% by weight offormaldehyde, 2% to 5% by weight of a plasticizer and 10% to 25% byweight of water; ii) 1.0 to 5.0 parts by weight of fire retardant; andiii) 10 to 40 parts by weight of water or alcohol as a solvent.
 14. Afire-resistant composite panel according to claim 2, wherein the resincompound comprises: i) 3.0% to 10.0% by weight (based on solid mass) ofa first condensate of a melamine resin or a phenol resin which isproduced by reaction of 25% to 45% by weight of melamine or phenol, 30%to 60% by weight of formaldehyde, 2% to 5% by weight of a plasticizerand 10% to 25% by weight of water; ii) 50% to 80% by weight of loess;iii) 1.0% to 5.0% by weight of fire retardant; and iv) 10% to 40% byweight of water or alcohol as a solvent.
 15. A fire-resistant compositepanel according to claim 2, wherein the resin compound comprises: i)3.0% to 10.0% by weight (based on solid mass) of a first condensate of amelamine resin or a phenol resin which is produced by reaction of 25% to45% by weight of melamine or phenol, 30% to 60% by weight offormaldehyde, 2% to 5% by weight of a plasticizer and 10% to 25% byweight of water; ii) 40% to 70% by weight of loess; iii) 3% to 20% byweight of an inorganic filler selected from the group consisting ofaluminum hydroxide, magnesium hydroxide and talc; iv) 1.0% to 5.0% byweight of fire retardant; and v) 10% to 40% by weight of water oralcohol as a solvent.
 16. A fire-resistant composite panel according toclaim 2, wherein the substrate material of the reinforcing layer iswoven fabric of glass fiber or alumina fiber having a weight per unitarea of 30 to 150 g/m².
 17. A fire-resistant composite panel accordingto claim 16, wherein the substrate material is woven glass fiber fabricmade of glass fiber having an E-glass composition produced by means of aweaving machine.
 18. A fire-resistant composite panel according to claim2, wherein the substrate material of the reinforcing layer is kraftpaper having a weight per unit area of 70 to 300 g/m².
 19. Afire-resistant composite panel according to claim 1, wherein a surfaceof the rear layer is coated with a thermosetting resin.
 20. Afire-resistant composite panel according to claim 1, wherein thethickness of the rear layer is in the range of 0.5 to 2.0 mm.
 21. Afire-resistant decorative composite panel comprising: a) a decorationlayer formed by impregnating or coating a patterned substrate with athermosetting resin; b) a substrate layer formed by impregnating orcoating a substrate material of a woven or nonwoven fabric of inorganicfiber, or a paper, with a resin compound which contains an inorganicfiller having loess as a main component and a thermosetting resinselected from the group consisting of a phenol resin, a modified phenolresin, a modified phenol-urea resin, a melamine resin, and a modifiedmelamine resin; and c) a rear layer of an aluminum sheet or a galvanizedsteel plate.
 22. A fire-resistant decorative composite panel accordingto claim 21, wherein a reinforcing layer formed by impregnating orcoating a woven inorganic fiber fabric or kraft paper with a resincompound of a modified melamine resin or a modified phenol resin isinterposed between the substrate layer and the decoration layer, betweensubstrate layers or between the substrate layer and the rear layer ofthe decorative composite panel.
 23. A fire-resistant decorativecomposite panel according to claim 21, wherein the amount of thethermosetting resin impregnated into the decoration layer is 50 to 200parts by weight with reference to 100 parts by weight of the patternedsubstrate.
 24. A fire-resistant decorative composite panel according toclaim 1, wherein the thermosetting resin is selected from the groupconsisting of a melamine resin, a phenol resin, an acryl resin, and aurethane resin.
 25. A fire-resistant decorative composite panelaccording to claim 1, wherein the patterned substrate is a paper havinga weight per unit area of 40 to 200 g/m², the material of which isselected from the group consisting of synthetic pulp, wood, textilefabrics and organic synthetic fiber.
 26. A fire-resistant decorativecomposite panel prepared by superposing from top to bottom: a) adecoration layer formed by impregnating or coating a patterned substratewith a thermosetting resin; b) 1 to 5 substrate layers formed byimpregnating or coating a substrate material of a woven or nonwovenfabric of inorganic fiber, or a paper, with a resin compound whichcontains an inorganic filler having loess as a main component and athermosetting resin selected from the group consisting of a phenolresin, a modified phenol resin, a modified phenol-urea resin, a melamineresin, and a modified melamine resin; and c) a rear layer of an aluminumsheet or a galvanized steel plate with a thermosetting resin coated onits surface, and then by forming it to be integrated by heat-pressing.27. A fire-resistant decorative composite panel prepared by superposingfrom top to bottom: a) a decoration layer formed by impregnating orcoating a patterned substrate with a thermosetting resin; b) 1 to 5substrate layers formed by impregnating or coating a substrate materialof a woven or nonwoven fabric of inorganic fiber, or a paper, with aresin compound which contains an inorganic filler having loess as a maincomponent and a thermosetting resin selected from the group consistingof a phenol resin, a modified phenol resin, a modified phenol-urearesin, a melamine resin, and a modified melamine resin; c) 1 to 12reinforcing layers formed by impregnating or coating a woven inorganicfiber fabric or kraft paper with a resin compound of a modified melamineresin or a modified phenol resin; and d) a rear layer of an aluminumsheet or a galvanized steel plate with a thermosetting resin coated onits surface, and then by forming it to be integrated by heat-pressing.28. A fire-resistant decorative composite panel prepared by superposingfrom top to bottom: a) a decoration layer formed by impregnating orcoating a patterned substrate with a thermosetting resin; b) 1 to 12reinforcing layers formed by impregnating or coating a woven inorganicfiber fabric or kraft paper with a resin compound of a modified melamineresin or a modified phenol resin; c) 1 to 5 substrate layers formed byimpregnating or coating a substrate material of a woven or nonwovenfabric of inorganic fiber, or a paper, with a resin compound whichcontains an inorganic filler having loess as a main component and athermosetting resin selected from the group consisting of a phenolresin, a modified phenol resin, a modified phenol-urea resin, a melamineresin and, a modified melamine resin; and d) a rear layer of an aluminumsheet or a galvanized steel plate with a thermosetting resin coated onits surface, and then by forming it to be integrated by heat-pressing.29. A fire-resistant decorative composite panel prepared by superposingfrom top to bottom: a) a decoration layer formed by impregnating orcoating a patterned substrate with a thermosetting resin; b) 1 to 5substrate layers formed by impregnating or coating a substrate materialof a woven or nonwoven fabric of inorganic fiber, or a paper, with aresin compound which contains an inorganic filler having loess as a maincomponent and a thermosetting resin selected from the group consistingof a phenol resin, a modified phenol resin, a modified phenol-urearesin, a melamine resin, and a modified melamine resin; c) 1 to 12reinforcing layers formed by impregnating or coating a woven inorganicfiber fabric or kraft paper with a resin compound of a modified melamineresin or a modified phenol resin; d) 1 to 5 substrate layers formed byimpregnating or coating a substrate material of a woven or nonwovenfabric of inorganic fiber, or a paper, with a resin compound whichcontains an inorganic filler having loess as a main component and athermosetting resin selected from the group consisting of a phenolresin, a modified phenol resin, a modified phenol-urea resin, a melamineresin, and a modified melamine resin; and e) a rear layer of an aluminumsheet or a galvanized steel plate with a thermosetting resin coated onits surface, and then by forming it to be integrated by heat-pressing.30. A fire-resistant decorative composite panel prepared by superposingfrom top to bottom: a) a decoration layer formed by impregnating orcoating a patterned substrate with a thermosetting resin; b) 1 to 12reinforcing layers formed by impregnating or coating a woven inorganicfiber fabric or kraft paper with a resin compound of a modified melamineresin or a modified phenol resin; c) 1 to 5 substrate layers formed byimpregnating or coating a substrate material of a woven or nonwovenfabric of inorganic fiber, or a paper, with a resin compound whichcontains an inorganic filler having loess as a main component and athermosetting resin selected from the group consisting of a phenolresin, a modified phenol resin, a modified phenol-urea resin, a melamineresin, and a modified melamine resin; d) 1 to 12 reinforcing layersformed by impregnating or coating a woven inorganic fiber fabric orkraft paper with a resin compound of a modified melamine resin or amodified phenol resin; and e) a rear layer of an aluminum sheet or agalvanized steel plate with a thermosetting resin coated on its surface,and then by forming it to be integrated by heat-pressing.